Orientadores: Fernanda Paula Collares-Queiroz, Alfredo de Almeida Vitali / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-16T13:25:39Z (GMT). No. of bitstreams: 1 Ormenese_RitaDeCassiaSalvucciCeleste_D.pdf: 39349692 bytes, checksum: 6b8d05b910ae7efffa7104944c570cc6 (MD5) Previous issue date: 2010 / Resumo: O resumo poderá ser visualizado no texto completo da tese digital / Abstract: The abstract is available with the full electronic document / Doutorado / Doutor em Tecnologia de Alimentos

For African farmers, proper drying is considered to be the biggest single factor in determining whether grain can be effectively stored without deterioration. The primary goal of the project is to develop and test the Pico solar crOp Dryer (POD). The overall goal is to improve the POD’s performance, making it acceptable to small holder farmers in Kenya and other developing countries, and positioning it for commercialization. In the POD tests shelled maize was placed in wooden or plastic trays and that were covered with plastic sheets. In the final design, seven small fans of the type used for cooling electronics moved air through the dryer. Power was supplied by a 12 volt, 30 Watt Solar Panel and a 12 volt 7 ampere hour lead acid battery. A charge controller allowed the fans to draw energy from both the solar panel and the battery. The POD was tested at Purdue from 2017 to 2019. The most recent Purdue test on freshly harvested maize was conducted in September 2018. The POD was able to dry 142 kg of 30.1% mc maize to 13.3% in 24.5 hours of drying over 3 calendar days giving an overall drying rate of 0.68 percentage points per hour. The POD dried the maize in 0.84 of the time required to dry maize on a tarp. In the summer of 2018, the components for assembling 5 POD’s were prepared and sent to Kenya for testing. The tests were conducted in Nakuru county in November 2018, and in Trans-Nzoia, Uasin Gishu, and Nandi counties in March 2019. Overall average drying rates for the tests varied, depending on weather conditions, from 0.58 to 0.97 percentage points per hour. A thin layer drying equation was adapted for use in investigating the effects of weather conditions and the airflow rate on the POD drying rate. Adoption of the POD by small holder farmers in Kenya and other developing countries should lead to a reduction in post-harvest losses caused by improper drying. Although testing has been primarily focused on drying maize, it could be adapted for drying other crops.

Monascus é um fungo ascomiceto tradicionalmente utilizado na China. Os povos orientais utilizam o produto de sua fermentação em arroz não aglutinado, ao qual dão o nome de \"Ang-kak\", e no inglês, \"Red yeast rice\". Sabe-se que este extrato contém substâncias hipocolesterolêmicas, como a Monacolina K, inibidor competitivo da enzima HMG-CoA. Este trabalho se insere neste contexto uma vez que consiste na otimização da fermentação e secagem do extrato de Monascus ruber. Embora já existam estudos sobre a atividade biológica deste extrato, os quais comprovam seus benefícios, não há muitos estudos que visam otimizar a sua fermentação em meio submerso e a secagem do extrato. Para tanto, foram avaliados diversos parâmetros na fermentação através de dois planejamentos fatoriais. No primeiro planejamento, as variáveis estudadas foram o meio de cultura (meio arrozina-glicose e meio sólido de arroz) e agitação (0 rpm e 10 rpm). A agitação promoveu um leve aumento na produção de monacolina-K, já o meio líquido foi mais eficiente na produção desta substância do que o meio sólido de arroz. Baseado neste experimento escolheu-se o meio fermentativo para os demais estudos. No segundo experimento as variáveis estudadas foram a adição no meio arrozina-glicose de zinco, amônio e glutamato. Neste experimento pôde-se verificar que o a produção de monacolina K e de pigmentos foi maior no meio com concentrações intermediárias de zinco e de glutamato e com concentrações maiores de amônio. No estudo da secagem, realizou-se um planejamento Box Benkhin, a fim de se avaliar a influência da proporção do adjuvante: fármaco, do tempo de incorporação do excipiente e da temperatura sobre características do extrato seco como: densidade aparente, densidade de compactação, fator de Hausner, umidade residual, atividade de água, atividade antioxidante e teor de monacolina K. Em relação à proporção do adjuvante: droga pode-se afirmar que a menor produz pós com menor atividade de água e teor de umidade, porém todos os pós obtidos tiveram seu teor de umidade e atividade de água dentro do ideal e a análise estatística mostrou que a proporção do adjuvante: droga não influenciou de forma significativa a atividade de água e o teor de umidade; a proporção 7,5:1 produz melhor rendimento e pós com melhores propriedades de fluxo, por possuírem menores valores de índice de compressibilidade e fator de hausner, já com a proporção 10:1 fornece pós com maior teor de monacolina e maior atividade antioxidante. Em relação à temperatura pode-se afirmar que utilizando-se 50°C obteve-se pós com melhores propriedades de fluxo, ou seja, menor índice de compressibilidade e menor e fator de hausner. Utilizando temperatura de 80°C obteve-se menor atividade antioxidante, maior rendimento e maior teor de monacolina K. Contudo, a análise estatística mostrou que a temperatura não influenciou de forma significativa o teor de monacolina K. Com uma temperatura maior, 110°C obteve-se menor teor de umidade e maior teor de pigmentos vermelhos. Em relação ao tempo de mistura do adjuvante pode-se afirmar que com 1 minuto obteve-se maior teor de pigmentos e pós com melhores propriedades de fluxo, com 5 minutos obteve-se menor teor de pigmentos, maior rendimento, maior teor de monacolina K e menor atividade de água, já com 10 minutos obteve-se menor teor de umidade e maior porcentagem de inibição. A análise estatística demonstrou que o tempo de mistura não influencia de forma significativa a atividade antioxidante. / Monascus ruber is an ascomycete fungus traditionally used in China. Eastern peoples use the product of its fermentation in rice non-agglutinated, which they call Ang-kak (red yeast rice, in English). It is known that this extract contains hypocholesterolemic substances such as the Monacoline K, a competitive inhibitor of the HMG-CoA enzyme. This work comes into this context since it consists in the optimization of the fermentative and drying processes of the Monascus rubers extract. Despite the existence of studies on the biological activity of this extract, which support its benefits, not many aimed at optimizing the fermentative process in submerged conditions and the drying of the extract. This work aimed at optimizing the fermentative process and the drying of the Monascus rubers extract. In order to do such, several parameters of the fermentative process were evaluated through two factorial plannings. In the first one, the variables studied were the modes of culture (liquid culture and solid-state culture) and agitation (0 rpm and 10 rpm). Agitation led to a slight increase in the production of Monacoline-K, and the liquid culture was more efficient in the production of this substance than the solid-state culture. Based on these findings, the fermentative substrate for the following experiments was chosen. In the second experiment, the variables studied were the addition of zinc, ammonium and glutamate in the liquid culture. It was observed that the production of monacoline-k and pigments was increased in the substrates with intermediary concentrations of zinc and glutamate and higher concentration of ammonium. In the drying study, a Box-Benkhin planning was adopted in order to assess the influence of the adjuvant: drug proportion, excipient incorporation time and temperature over the characteristics of the dried extract, such as: apparent density, compactation density, Hausner factor, residual humidity, water activity, antioxidant activity and monacoline-K levels. Regarding the adjuvant: drug proportion, it can be stated that the 5:1 proportion produces powders with smaller water activity and humidity levels, however, all the powders obtained presented humidity levels and water activity within the ideal and, besides that, the statistical analysis showed that the adjuvant: drug proportion had no significant influence on water activity or humidity levels; the proportion of 7,5:1 produces greater quantities and powders with better flow properties, since they have lower values of IC and FH; and with the proportion of 10:1, powders with higher levels of monacoline-K and greater antioxidant activity can be obtained. Concerning temperature, it was observed that powders with better flow properties (lower IC and FH) were obtained at 50°C. At 80°C, lower antioxidant activity, greater quantities and higher levels of monacoline-K were observed, however, the statistical analysis showed that the temperature had no significant effect on the levels of monacoline-K. With a higher temperature (110°C), lower humidity levels and higher red pigment levels were obtained. Concerning the mix time adjuvant: drug proportion, it can be stated that with 1 minute higher levels of pigment and powders with better flow properties were obtained; lower levels of pigment, greater quantities, higher levels of monacoline-K and lower water activity were obtained with 5 minutes and; lower humidity level and greater percentage of inhibition were observed with 10 minutes, however, the statistical analysis showed that the mix time has no significant influence on the antioxidant activity.

Biomassa är en växande energikälla i samhället. Biomassa så som sågspån behöver ofta torkas och pelleteras innan det kan användas som energikälla vid förbränning. Sågspån torkas innan pelleteringen för att kunna ge ett bra värmevärde och för att kunna förbrännas utan ökade halter av utsläpp. I takt med ökad användning av detta bränsle finns det en ökad efterfrågan på energieffektiva torkningsmetoder. På Karlstad Universitet har det därför byggts en pilotanläggning av en pneumatisk tork med syfte att fungera som ett steg i en energieffektiv torkningsmetod kallad ”Two Step Drying Technique” eller TSDT. Det här arbetet har handlat om att utvärdera effektivitetsmått och driftinformation för torken på Karlstads Universitet. Torken har fått namnet PD-KaU som står för ”Pneumatic Dryer at Karlstad University”. Genom praktiska mätningar av PD-KaU:s prestanda vid torkning av sågspån med uppvärmd luft har effektivitetsmåtten  och  beräknats vid olika driftfall. Även skillnader i torr- och våttemperaturer i olika delar av torken har utvärderats. En effektbalans har använts för att kontrollera mätningarnas stabilitet. De olika driftfallen fås genom variation av torkningsparametrar så som mängden sågspån som torkas, ca 1 och 2 kg torrsubstans per minut, och variation av luftens temperatur, 80, 100 och 120 °C, samt hastighet genom torken, 6, 8 och 10 m/s. Även 12 och 14 m/s testades vid 80 °C. Torkens minimala fluidiseringshastighet för sågspån har beräknats och minimala hastigheten som krävs för att sågspånet ska transporteras genom torkens rörsystem har mätts. Mätningar på sågspånets fukthalter före och efter torken tillsammans med massflöden sågspån genom torken har gjorts för alla driftfall. Använd effekt från överhettare och fläkt som finns i anslutning till torken har också mätts och dessa mätningar ligger till grund för beräkningarna av  och . Med hjälp av elektronisk mätning av torra temperaturer och tryckfall över systemet har också våttemperaturer i olika delar av systemet kunnat beräknas. All data från dessa mätningar har också använts till effektbalansen. Vid massflöden på ca 1 kg/min TS sågspån genom torken är  som högst om hastigheten på luften är låg. Högsta  för de driftfall som testats vid detta massflöde fås när lufttemperaturen är 120 °C och lufthastigheten är kring 8,6 m/s. Genom öka på rörsystemets längd i torken skulle ett högre  kunna uppnås vid högre hastigheter. Vid ett massflöde på ca 2 kg/min fås högsta  vid lufttemperaturen 100 °C och lufthastighet kring 8,3 m/s. Om höga massflöden sågspån används kommer sågspånet i större grad i kontakt med luften och  är högt oberoende av lufthastigheten i de intervall som testats. Optimala lufttemperaturen visade sig vara vid 100 °C.  är som lägst vid låga hastigheter och höga massflöden. Lägsta värdet på  för båda massflödena fås när lufttemperaturen var 120 °C och lufthastigheten 7,0 m/s. Genom att minska på rörsystemets längd skulle  kunna minska. Utvärderingen av våttemperaturen visar att det mesta av torkningen sker i början av systemet. / Biomass is a growing source of energy in our society. Biomass such as sawdust often needs to be dried and pelletized before it can be burnt to produce energy. Sawdust is dried before pelleting in order to give a good calorific heat value and to be able to be incinerated without increased levels of emissions. With increased use of this fuel there is an increasing demand for energy efficient drying methods. A pilot plant of a pneumatic dryer has therefore been built at Karlstad University with a purpose to serve as a step in an energy efficient drying method called “Two Step Drying Technique” or TSDT. This thesis aimed to evaluate performance and operating information for the dryer at Karlstad University. The dryer has been named PD-KaU which stands for "Pneumatic Dryer at Karlstad University." Through practical measurements of the PD-KaU's performance when drying sawdust with heated air, efficiency indices  and  has been calculated at various operating conditions. Differences in the dry and wet-bulb temperature in different parts of the dryer have also been evaluated. An energy balance, or more correctly a power balance has been used to evaluate the stability of the measurements. The various operating conditions is obtained by variation of different drying parameters such as the amount of sawdust dried, about 1 and 2 kg solids per minute, and the variation of air temperature, 80, 100 and 120 ° C, and the speed through the dryer, 6, 8 and 10 m/s. Also, 12 and 14 m/s were tested at 80 ° C. The minimum fluidizing velocity for the dryer when using sawdust has been calculated and the minimum speed required for the transportation of sawdust through the dryer tubes have been measured. Measurements on the sawdust moisture levels before and after the dryer along with the mass flow of sawdust through the dryer have been made for all operating conditions. The power from the super heater and fan that is used with the dryer has also been measured and these measurements together with the moisture levels and mass flows are used for calculating  and. By using electronic equipment measurements of dry temperatures and pressure drop across the system has also been possible and they have been used to calculate the wet-bulb temperature in different parts of the system. All data from these measurements were also used for the power balance. At mass flow rates of about 1 kg/min solids of sawdust through the dryer  is highest if the speed of the air is low. The highest value on  for the various operating conditions at this mass flow rate was found to be at an air temperature of 120 °C and air speed of 8,6 m/s. By increasing the length of tubing in the dryer, a higher  be achieved at higher speeds. If 2 kg/min of solids are put into the system the sawdust comes in contact with the air to a greater extent and  is highly independent of the air velocity in the ranges tested. At this higher mass flow rate the highest value of  was found to be at an air temperature of 100 °C and an air speed of 8,3 m/s Optimum air temperature was found to be at 100° C.  is lowest at low speeds and high mass flows. The lowest value for  for both tested mass flow rates was found to be when the air temperature was 120 °C and the air speed was 7,0 m/s. By reducing the tubing length SPC could be reduced. The evaluation of the wet-bulb temperature shows that most of the drying takes place in the beginning of the system.

Arbetet bygger på en jämförelse för Andritz AB där två olika lyftanordningssystem till maskinen Fläkt Dryer har undersökts. Ett där pneumatik används och ett där skruvdomsarrangemang används. Fyra koncept har tagits fram och jämförts baserat på deras egenskaper med hjälp av systemtänkande produktutveckling. Det har också gjorts en ekonomisk jämförelse mellan koncepten där tre olika leverantörer har används.

The use of washable baghouses for fines collection in milk powder plants has been investigated. The main aim of this study was to increase the fundamental understanding of both operation and design of washable baghouses for application in milk powder plants. This work has focussed on the industrial scale. Industrial plant operating data has been collected, plant designs compared and analyses conducted on powder produced at the industrial scale. The amount of powder that becomes fines, the small size fraction of powder entrained in spray dryer outlet air streams, has been shown to be significantly greater than the traditionally vague estimate of 10 % to 20 %. The ratio of fines flows to total powder flows ranged from 49 ± 8 % to 86 ± 2 % depending on the powder type and plant operating conditions. A simple yet reliable method was developed to quantify fines flows based on measured powder size distributions of samples taken from around the plant. These estimates were supported by readings from an online optical scintillation instrument, which was shown to be capable of measuring fines flows at concentrations approximately four times the supposed maximum stated by the instrument’s manufacturer. Observations in another part of this work supported previous Fonterra observations showing that the amount of bulk fat in skim milk powder (SMP) has a large influence on the baghouse differential pressure. Fines flows measured by the optical scintillation instrument and analysis of other plant operating data showed that a change in bulk fat in SMP does not appear to cause any change in fines concentration. Observations of the surface of SMP by scanning electron microscopy, and electron spectroscopy for chemical analysis, both showed that fat is over-represented on the surface of the particles, and that only small increases in the bulk fat content are required to cause large increases in the surface fat coverage. It is hypothesised that increased fat on the surface of particles increases the clumping of SMP before deposition on the bags. Consequently, the powder forms more porous cakes and is less likely to penetrate into the interior of the filter bags, which also makes it easier to pulse clean powder from the filter bags. Therefore, the baghouse differential pressure is reduced. The design of pulse-jet baghouses from the literature was found to rely heavily on the authors past experience and approach, giving rise to large variation in recommended values of the key design parameters. A procedure for determining the optimal combination of these parameters was developed. This procedure showed that the main Fonterra washable baghouses are far from optimal because of their high air-to-cloth ratios, long bags and high elutriation and annular velocities. This procedure also showed that the Fonterra vibrating fluid bed washable baghouses are much closer to the optimum, which is the probable reason these washable baghouses have had almost no operational issues. Observations of the movement of the bags from below showed significant movement for bags near the inlet of the baghouse, indicating that this was the probable cause of the high bag damage in this zone. It is suggested that increasing the outer gap (distance between the baghouse wall and the bag on the edge of the bag bundle) be investigated further in an attempt to slow the annular velocity around the edge of the bag bundle and reduce bag movement. It is also recommended that stainless steel inspection hatches installed in the wall of a baghouse for this research, be included in all current and future washable baghouses because use of these hatches reduced the overall clean-in-place turn around time by 20 %. Computational fluid dynamics simulations of the air flow patterns within the Clandeboye Dryer 2 chamber were carried out using a commercial code CFX10.0. These simulations are possibly the first to include the influence of a spray dryer’s internal fluid bed airflow on the flow patterns within a spray dryer. As expected, the simulations showed the main air jet oscillated and precessed about the central axis with no apparent distinct frequency. In turn, the recirculation zones between the main jet and the chamber walls fluctuated in size. Different fluid bed flows within the industrial range had only a local influence on the air only flow field by reducing the length of the main jet. A different outlet boundary condition (including a flow resistance representing the baghouse) also appeared to have little influence on the overall flow field. Good agreement was found between the movements of the main jet via simulations and from telltale tufts installed in the plant dryer. This supported other indications that the simulations were an accurate representation of the actual flows. It was concluded that this project achieved its main aim of improving the fundamental understanding of washable baghouse operation and design, especially for application in milk powder plants. Also this project, as well as a change in production schedules, has helped to reduce downtime associated with the washable baghouses in the Fonterra Clandeboye Dryer 2 plant by an estimated 50 hours per annum.

Med ett energikombinat vid Lillesjöverket vill Uddevalla Energi energieffektivisera samt sänka temperatur på återkommande fjärrvärmevatten, för att kunna utnyttja rökgaskondensorn effektivare. Uppdraget var att utreda mängden tillgänglig energi under sommarhalvåret och utföra en matematisk kalkyl som ska ligga till grund för val av tork. Valet stod mellan två alternativ av tork där storlek på värmeväxlararea och investeringskostnad skilde dem åt. Sedan följde dimensionering av fjärrvärmeledning samt cirkulationspump från fjärrvärmenätet till tork. Syftet var att ge Uddevalla Energi ett tekniskt beslutsunderlag för val av storlek på tork samt dimensionering av energiöverföring till densamma. Som metod användes flera olika beräkningsmodeller vid kalkylering av resultaten. Vid jämförelse mellan de två torkalternativen visade det sig att med en ökad investeringskostnad med 2,18 %, för en större värmeväxlararea i tork, ökade mängden energi som fanns tillgänglig till tork under sommarhalvåret med 16,7 %. Detta medförde att kostnaderna för tillskjuten energi sänktes med 65,9 % för att Uddevalla Energi skulle nå sitt mål på 60 GWh. För att nå målet krävdes enligt kalkyl en installation av torkalternativ 2 samt en sänkning av antalet dagar då verket står still på grund av underhåll. / With an energy combine at Lillesjöverket, Uddevalla Energi wants to improve energy efficiency and lower the temperature of the returning district heating water in order to utilize the flue gas condenser more effectively. The assignment was to investigate the availability of power during the summer months and perform a mathematical calculation that will form the basis for the selection of dryer. The selection stood between two options of dryer where the size of the heat exchanger area and investment costs separated them. Also performed were sizing of the district heating water pipeline and the circulation pump from the district heating water network to the dryer. The purpose was to present Uddevalla Energi with a technical basis for selection of the size of the dryer and sizing of energy transfer to the dryer. As method several different calculations were used when calculating the results. When comparing the two options, it turned out that with an increased investment cost of 2.18%, for a larger heat exchange area in the dryer, the amount of energy available to the dryer during the summer months increased by 16.7%. This meant that the cost for energy contributed, for Uddevalla Energi to achieve their goal of 60 GWh, is reduced by 65.9%. To achieve their goal it was required by calculations to install dryer option number two and a reduction in the number of days in which the work is at a standstill due to maintenance.

Orientador: Vânia Regina Nicoletti Telis / Banca: Caciano Pelayo Zapata Noreña / Banca: Joel Fernando Nicoleti / Banca: José Francisco Lopes Filho / Banca: José Antônio Gomes Vieira / Resumo: Os objetivos deste trabalho foram analisar a influência do tipo e da quantidade de aditivos, além de diferentes métodos de secagem da polpa de maracujá em pó, nas isotermas, propriedades termodinâmicas de sorção e nos atributos de qualidade do produto obtido. No capítulo 1 descreve-se o efeito de diferentes aditivos - maltodextrina DE 10 e goma arábica - sobre as isotermas de sorção nas temperaturas de 20, 30, 40 e 50 ºC de polpa de maracujá em pó obtida por secagem a vácuo. O modelo de GAB se ajustou aos dados de sorção. As isotermas apresentaram comportamento da curva do tipo II, na classificação de Brunauer. Observou-se que a adição de maltodextrina DE 10 e de goma arábica à polpa de maracujá desidratada reduziu a umidade de equilíbrio em relação à umidade da polpa pura e não houve diferença considerável entre as umidades de equilíbrio das amostras da polpa com 18% de goma arábica e polpa com 18% ou 55% de maltodextrina. O aumento da concentração da maltodextrina não teve influência sobre os valores de umidade de equilíbrio. O calor isostérico de sorção da polpa em pó aumentou com o decréscimo da umidade, ao mesmo tempo em que apresentou menores valores para a polpa em pó com aditivos do que os observados para a polpa pura. Através da teoria da compensação isocinética, pode-se concluir que o processo de sorção de água pela polpa de maracujá em pó é um processo espontâneo e controlado pela entalpia para todas as amostras testadas. No capítulo 2 foi analisada a influência de três métodos de secagem: em estufa a vácuo (60 ºC), spray drying (140 ºC) e liofilização sobre as isotermas da polpa de maracujá em pó com 55% de maltodextrina DE 10. O pó produzido em spray dryer apresentou maior capacidade de sorção em relação aos pós desidratados em estufa a vácuo e em liofilizador. No capítulo 3 foi avaliada a influência... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objectives of this work were to analyze the influence of type and quantity of additives, in addition to different drying methods, on the production of powdered passion fruit pulp, on its water sorption isotherms and on its themodynamical properties, as well as evaluating the quality attributes of the obtained product. Chapter 1 describes the effect of different additives - maltodextrin DE 10 and Arabic gum - on the sorption isotherms at temperatures of 20, 30, 40 e 50 ºC of passion fruit pulp powder obtained by vacuum drying. The sorption data were well adjusted by GAB model. The isotherms presented behavior of type II curves according to the Brunauer classification. The addition of maltodextrin DE 10 and Arabic gum to the passion fruit pulp powder decreased the equilibrium water content when compared to the pure powdered pulp and no considerable differences between the equilibrium moisture content of samples with 18% of arabic gum and with 18% or 55% of maltodextrin were observed. The increase in maltodextrin concentration did not affect the equilibrium water contents. The isosteric heat of sorption of the powdered pulp increased with decreasing water content, at the same time that lower values were obtained to powdered pulp with additives than to pure powdered pulp. Through the isokinetic compensation theory it could be concluded that the water sorption process by the powdered passion fruit pulp is an enthalpy controlled, spontaneous process for all tested samples. In chapter II, the influence of three drying methods: vacuum drying (60 ºC), spray drying (140 ºC) and freeze drying over the powdered passion fruit pulp isotherms with 55% of maltodextrin DE 10, was analyzed. The passion fruit pulp powder produced by spray drying presented higher sorption ability than vacuum dried and freeze dried pulp. In chapter 3, the influence of different concentrations and different dextrose... (Complete abstract click electronic access below) / Doutor

O mirtilo é uma fruta nativa da América do Norte e ainda pouco conhecida no Brasil. O principal fator de interesse desta fruta é seu elevado potencial antioxidante associado à presença de compostos bioativos, em especial as antocianinas, responsáveis por efeitos benéficos para a saúde humana no tratamento de diversas doenças. O processamento do mirtilo para produção de suco gera em torno de 20% de resíduos (bagaço), o qual contém cerca de 60% das antocianinas totais presentes na fruta fresca. Dentro deste contexto, o presente trabalho tem como objetivo principal avaliar a recuperação das antocianinas presentes no bagaço proveniente da produção de suco de mirtilo, bem como o processo para manter sua estabilidade frente a certas condições ambientais para então servirem como aditivo alimentar. Para isso, a partir do bagaço de mirtilo, foram testadas diferentes condições de extração, utilizando água a 1% de ácido cítrico como solvente, nas temperaturas de 60 e 80 °C e tempos de 5, 15 e 45 minutos. Para extração das antocianinas a condição de 80 ºC durante 5 minutos apresentou o melhor resultado, totalizando 1.944 mg de cianidina-3-glicosídeo/100 g de bagaço em base seca, enquanto para extração de compostos fenólicos totais obteve-se o melhor resultado na temperatura de 80 ºC e 45 minutos analogamente à atividade antioxidante. A etapa subsequente à extração foi a microencapsulação das antocianinas presentes no extrato (80 ºC, 5 minutos) pela técnica de secagem por atomização (spray drying), utilizando como material de parede a maltodextrina e a goma arábica na concentração de 15% m/v. Quanto aos parâmetros de secagem, testaram-se as temperaturas do ar de entrada de 140 e 160 °C. Os pós obtidos foram analisados segundo os aspectos físicos de retenção de antocianinas, morfologia, umidade, higroscopicidade, solubilidade em água e atividade de água. Todas as condições testadas apresentaram um microparticulado com características físicas adequadas para sua estabilidade. Para estudo da degradação das antocianinas quando expostas à radiação ultravioleta (UV) foram feitas análises de concentração de antocianinas e variação de cor durante 41 dias, verificando-se duas cinéticas de degradação. Analisando a cinética mais lenta, o tempo de meia vida das micropartículas de antocianinas ficou entre 7,8 e 14,9 meses, sendo o pó obtido com maltodextrina e temperatura de ar de entrada de 140 ºC o qual se mostrou mais estável à radiação UV. / The blueberry is a native fruit from North America and still little known in Brazil. The main interest factor in this fruit is its high antioxidant potential associated with the presence of bioactive compounds, especially anthocyanins, responsible for beneficial effects on human health in the treatment of several diseases. From blueberry juice process, around 20% of waste (pomace) is generated, which contains about 60% of total anthocyanins present in the fresh fruit. This work aims to evaluate the recovery of anthocyanins present in the waste from blueberry juice production and the process to maintain its stability against some environmental conditions to be used as a replacement to synthetic dyes. The blueberry pomace was subjected to different anthocyanins extraction condition, using water with 1% citric acid as solvent, temperatures of 60 to 80 °C and times of 5, 15 and 45 minutes. The best extracted condition was at 80 °C for 5 minutes, yielding a total of 1,944 mg of anthocyanins extracted from pomace cyanidin-3-glucoside/100 g on dry weight basis, while for the phenolic compounds extraction the best result was obtained in the temperature of 80 ºC and 45 minutes analogously to the antioxidant activity. After the extraction, the subsequent step was the microencapsulation of anthocyanins in the extract with the technique of spray drying using as wall material maltodextrin and arabic gum. Regarding the parameters of drying, the inlet air temperature was 140 to 160 °C. The powders were analyzed according to the physical aspects of anthocyanin retention, morphology, moisture content, hygroscopicity, solubility in water and water activity. All conditions tested showed a microparticle with suitable physical characteristics for its stability. To study the anthocyanins degradation when exposed to ultraviolet irradiation, analysis of anthocyanin content and color variation were done during 41 days. Two degradation kinetics where observed. Analyzing the slower kinetics, the half life of anthocyanins micropaticles was between 7.8 and 14.9 months, being the powder obtained with maltodextrin and 140 °C inlet air temperature the most stable to UV radiation.

Made available in DSpace on 2014-06-11T19:31:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-08-28Bitstream added on 2014-06-13T18:42:35Z : No. of bitstreams: 1 pedro_mam_dr_sjrp.pdf: 1284122 bytes, checksum: 45709686cf62bab3c06f4aeffcf8c502 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Os objetivos deste trabalho foram analisar a influência do tipo e da quantidade de aditivos, além de diferentes métodos de secagem da polpa de maracujá em pó, nas isotermas, propriedades termodinâmicas de sorção e nos atributos de qualidade do produto obtido. No capítulo 1 descreve-se o efeito de diferentes aditivos - maltodextrina DE 10 e goma arábica - sobre as isotermas de sorção nas temperaturas de 20, 30, 40 e 50 ºC de polpa de maracujá em pó obtida por secagem a vácuo. O modelo de GAB se ajustou aos dados de sorção. As isotermas apresentaram comportamento da curva do tipo II, na classificação de Brunauer. Observou-se que a adição de maltodextrina DE 10 e de goma arábica à polpa de maracujá desidratada reduziu a umidade de equilíbrio em relação à umidade da polpa pura e não houve diferença considerável entre as umidades de equilíbrio das amostras da polpa com 18% de goma arábica e polpa com 18% ou 55% de maltodextrina. O aumento da concentração da maltodextrina não teve influência sobre os valores de umidade de equilíbrio. O calor isostérico de sorção da polpa em pó aumentou com o decréscimo da umidade, ao mesmo tempo em que apresentou menores valores para a polpa em pó com aditivos do que os observados para a polpa pura. Através da teoria da compensação isocinética, pode-se concluir que o processo de sorção de água pela polpa de maracujá em pó é um processo espontâneo e controlado pela entalpia para todas as amostras testadas. No capítulo 2 foi analisada a influência de três métodos de secagem: em estufa a vácuo (60 ºC), spray drying (140 ºC) e liofilização sobre as isotermas da polpa de maracujá em pó com 55% de maltodextrina DE 10. O pó produzido em spray dryer apresentou maior capacidade de sorção em relação aos pós desidratados em estufa a vácuo e em liofilizador. No capítulo 3 foi avaliada a influência... / The objectives of this work were to analyze the influence of type and quantity of additives, in addition to different drying methods, on the production of powdered passion fruit pulp, on its water sorption isotherms and on its themodynamical properties, as well as evaluating the quality attributes of the obtained product. Chapter 1 describes the effect of different additives - maltodextrin DE 10 and Arabic gum - on the sorption isotherms at temperatures of 20, 30, 40 e 50 ºC of passion fruit pulp powder obtained by vacuum drying. The sorption data were well adjusted by GAB model. The isotherms presented behavior of type II curves according to the Brunauer classification. The addition of maltodextrin DE 10 and Arabic gum to the passion fruit pulp powder decreased the equilibrium water content when compared to the pure powdered pulp and no considerable differences between the equilibrium moisture content of samples with 18% of arabic gum and with 18% or 55% of maltodextrin were observed. The increase in maltodextrin concentration did not affect the equilibrium water contents. The isosteric heat of sorption of the powdered pulp increased with decreasing water content, at the same time that lower values were obtained to powdered pulp with additives than to pure powdered pulp. Through the isokinetic compensation theory it could be concluded that the water sorption process by the powdered passion fruit pulp is an enthalpy controlled, spontaneous process for all tested samples. In chapter II, the influence of three drying methods: vacuum drying (60 ºC), spray drying (140 ºC) and freeze drying over the powdered passion fruit pulp isotherms with 55% of maltodextrin DE 10, was analyzed. The passion fruit pulp powder produced by spray drying presented higher sorption ability than vacuum dried and freeze dried pulp. In chapter 3, the influence of different concentrations and different dextrose... (Complete abstract click electronic access below)